A customer walks into an op shop and purchases an overnight bag. At the register, an unsupervised store volunteer unzips the side pocket. Fifty thousand dollars in Australian cash falls out. All in A$100 bills.

The find sparks the ultimate in real-life integrity tests.

After three months, Queensland police can conclude the money literally fell into the hands of one of the most honest shop assistants in Australia, but at the same time, brought forth some of the most grasping charlatans to draw breath.

Sergeant Dan McNamara, a police officer for 27 years, said he had never seen a case like this before on the Sunshine Coast.

Apart from the cash, the only other clues were the anonymous handwritten scrawls on scraps of paper found inside the bag.

News of the discovery at the Red Cross secondhand shop in the town of Pomona spread through the community. Unfortunately for police, more than one owner emerged to claim their misplaced cash.

''We had a number of people come forward,'' McNamara said.

''Just let's say it was fewer than six. Unfortunately for them, the denominations were wrong, the circumstances doubtful and the likelihood of them losing it unlikely.''

McNamara said police had to work through donations to the op shop. He said an elderly resident who had moved house was identified as a possibility.

Forensic scientists examined examples of the donor's handwriting and matched them to the paper scraps inside the bag.

The money and owner were reunited this week. Should we be surprised that some people are honest and others not, particularly when A$50,000 (NZ$58k) is involved?